1. Technical Field
The present disclosure relates to power source circuits and, particularly, to a power source circuit having high efficiency in converting alternating current (AC) to direct current (DC).
2. Description of Related Art
Power source circuits generally include a rectifier. The rectifier is used to connect to an external AC power source, such as a 220 volts (V) and 50 Hertz (Hz) AC power source. The rectifier rectifies the AC current and outputs DC current to a load. At the moment that the AC power source is connected, inrush current that may exceed the rated current of the load flows into the load, which may damage the load. To reduce strength of the inrush current, a resistor is usually employed and connected between the AC power source and the rectifier. However, when the load is in operation, the resistor consumes energy and converts it into heat, which is useless or may even be harmful. The conversion efficiency of the power source circuit is reduced.
Therefore, it is desirable to provide a power source circuit which can overcome the above-mentioned limitations.